r - How to count TRUE values in a logical vector -


In R, what is the most effective / idiomatic way to calculate the number of TRUE Logical vector? I can think of two ways: 

  z

Who likes? Is anything better?

There are some problems when the NA value in the logical vector.
For example, see: 

  z   
 So I think that's safe  
  sum (z, na.rm = TRUE)  
 
 (which returns 1). I think the  table  solution is less efficient (see the code for the  table  function). 
 
 Also, if you do not have a "table" solution, if there are no real values ​​in the logical vector  z  or simply  z < -c (wrong, false)  
 
  Table (Z) ["TRUE"] # gives you NA for both cases

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